Control method, system, electronic device and storage medium of multi-link mechanism

Abstract

The present invention discloses a control method, system, electronic device, and storage medium for a multi-link mechanism. The multi-link mechanism includes a plurality of interconnected links and a linear actuator for driving the movement of the links. The method includes: obtaining an initial change trend of the angular velocity of the target link when the linear actuator moves at a constant speed based on a determined correspondence between the moving stroke of the linear actuator and the pitch angle of the target link; and adjusting the moving speed of the linear actuator based on the initial change trend of the angular velocity, so that the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend. The present invention adjusts the moving speed of the linear actuator based on the initial change trend of the angular velocity of the target link when the linear actuator moves at a constant speed, so that the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend, thereby improving the control efficiency of the multi-link mechanism and reducing the control cost.

Description

Technical Field

[0001] The present invention relates to the technical field of multi-link mechanisms, and in particular to a control method, system, electronic equipment and storage medium for a multi-link mechanism. Background Art

[0002] To achieve tilt, pitch, or rotation of the load, a multi-link design is typically used. However, due to the varying lengths of the links, fulcrum locations, and other factors, the angular velocity of the load can fluctuate significantly when the motor is moving at a constant speed. To reduce this angular velocity fluctuation, a velocity sensor is often added, but this increases hardware costs. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the defects of high cost and complicated operation in the prior art method of reducing the angular velocity change rate of the load end of a multi-link mechanism, and to provide a control method, system, electronic device and storage medium for a multi-link mechanism.

[0004] The present invention solves the above technical problems through the following technical solutions:

[0005] A first aspect of the present invention provides a control method for a multi-link mechanism, wherein the multi-link mechanism includes a plurality of interconnected links and a linear actuator for driving the links to move. The control method includes:

[0006] Determining a corresponding relationship between a movement stroke of the linear actuator and a pitch angle of a target connecting rod;

[0007] Obtaining, according to the corresponding relationship, an initial change trend of the angular velocity of the target link when the linear actuator moves at a constant speed;

[0008] The moving speed of the linear actuator is adjusted according to the initial change trend of the angular velocity, so that the real-time change trend of the angular velocity of the target link after adjustment is more stable than the initial change trend.

[0009] Preferably, the control method further includes:

[0010] The moving speed of the linear actuator is adjusted according to the initial change trend of the angular velocity, so that the angular velocity change rate of the target link is less than a preset angular velocity change rate, or the angular velocity change rate of the target link is minimized.

[0011] Preferably, the angular velocity of the target link is obtained based on a derivative calculation of the pitch angle of the target link.

[0012] Preferably, the step of adjusting the moving speed of the linear actuator according to the initial change trend of the angular velocity so that the real-time change trend of the adjusted angular velocity of the target link is more stable than the initial change trend comprises:

[0013] Dividing the moving stroke of the linear actuator into a plurality of sub-strokes;

[0014] Obtaining each initial change trend of the angular velocity of the target connecting rod in each sub-stroke;

[0015] The moving speed of the linear actuator in each sub-stroke is adjusted according to each initial change trend, so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend.

[0016] Preferably, the control method further includes:

[0017] Obtaining the maximum angular velocity and the root mean square angular velocity of the target connecting rod;

[0018] The angular velocity change rate of the target link is calculated according to the maximum angular velocity and the root mean square of the angular velocity.

[0019] Preferably, the multi-link mechanism is a four-link mechanism, which includes a first link, a second link, a third link and a fourth link, the second link is the target link, and the first link, the second link, the third link, the fourth link and the linear actuator are connected to each other in sequence.

[0020] Preferably, both end points of the second connecting rod are not fixed, and the first connecting rod, the third connecting rod and the fourth connecting rod all have one end point fixed and the other end point not fixed.

[0021] A second aspect of the present invention provides a control system for a multi-link mechanism, wherein the multi-link mechanism includes a plurality of interconnected links and a linear actuator for driving the links to move, and the control system includes:

[0022] A first determining module is used to determine a corresponding relationship between a moving stroke of the linear actuator and a pitch angle of a target connecting rod;

[0023] a second determining module, configured to obtain, based on the corresponding relationship, an initial change trend of the angular velocity of the target link when the linear actuator moves at a constant speed;

[0024] The first adjustment module is configured to adjust the moving speed of the linear actuator according to the initial variation trend of the angular velocity, so that the real-time variation trend of the angular velocity of the target link after adjustment is more stable than the initial variation trend.

[0025] Preferably, the control system further comprises:

[0026] The second adjustment module is used to adjust the moving speed of the linear actuator according to the initial change trend of the angular velocity, so that the angular velocity change rate of the target link is less than the preset angular velocity change rate, or the angular velocity change rate of the target link is minimized.

[0027] Preferably, the angular velocity of the target link is obtained based on a derivative calculation of the pitch angle of the target link.

[0028] Preferably, the first adjustment module includes:

[0029] a dividing unit, configured to divide the moving stroke of the linear actuator into a plurality of sub-strokes;

[0030] an acquiring unit, configured to acquire each initial change trend of the angular velocity of the target connecting rod within each sub-stroke;

[0031] An adjustment unit is used to adjust the moving speed of the linear actuator in each sub-stroke according to each initial change trend, so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend.

[0032] Preferably, the control system further comprises:

[0033] A first acquisition module is used to obtain the maximum angular velocity and the root mean square angular velocity of the target connecting rod;

[0034] The second acquisition module is configured to calculate the angular velocity change rate of the target link according to the maximum angular velocity and the root mean square of the angular velocity.

[0035] Preferably, the multi-link mechanism is a four-link mechanism, which includes a first link, a second link, a third link and a fourth link, the second link is the target link, and the first link, the second link, the third link, the fourth link and the linear actuator are connected to each other in sequence.

[0036] Preferably, both end points of the second connecting rod are not fixed, and the first connecting rod, the third connecting rod and the fourth connecting rod all have one end point fixed and the other end point not fixed.

[0037] A third aspect of the present invention provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and for running on the processor, wherein when the processor executes the computer program, the control method of the multi-link mechanism as described in the first aspect is implemented.

[0038] A fourth aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the control method of the multi-link mechanism as described in the first aspect.

[0039] On the basis of conforming to the common sense in this field, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present invention.

[0040] The positive progress effect of the present invention is:

[0041] The present invention can reduce the angular velocity change rate of the target link of a multi-link mechanism without adding a speed sensor to the target link. Specifically, the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target link is determined; based on the corresponding relationship, the initial change trend of the angular velocity of the target link when the linear actuator moves at a constant speed is obtained; the moving speed of the linear actuator is adjusted according to the initial change trend of the angular velocity, so that the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend, thereby improving the control efficiency of the multi-link mechanism and reducing the control cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 Flowchart of the control method of the multi-link mechanism according to embodiment 1 of the present invention.

[0043] Figure 2 This is a flowchart of step 103 of the method for controlling a multi-link mechanism according to embodiment 1 of the present invention.

[0044] Figure 3 This is a first structural schematic diagram of the multi-link mechanism of Examples 1 and 2 of the present invention.

[0045] Figure 4 This is a second structural schematic diagram of the multi-link mechanism of Examples 1 and 2 of the present invention.

[0046] Figure 5 Schematic diagram of the initial change trend of the angular velocity of the target link of the multi-link mechanism of Examples 1 and 2 of the present invention.

[0047] Figure 6 Schematic diagram of the real-time change trend of the angular velocity of the target link of the multi-link mechanism of Examples 1 and 2 of the present invention.

[0048] Figure 7 This is a module schematic diagram of the control system of the multi-link mechanism of Example 2 of the present invention.

[0049] Figure 8 This is a structural diagram of an electronic device for implementing a control method for a multi-link mechanism according to embodiment 3 of the present invention. DETAILED DESCRIPTION

[0050] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the examples.

[0051] Example 1

[0052] This embodiment provides a control method for a multi-link mechanism, which includes a plurality of interconnected links and a linear actuator for driving the links to move. Figure 1 As shown, the control method includes:

[0053] Step 101: Determine the corresponding relationship between the movement stroke of the linear actuator and the pitch angle of the target connecting rod;

[0054] In this embodiment, when the movement stroke of the linear actuator changes uniformly, the change of the pitch angle of the target link is non-uniform.

[0055] It should be noted that the pitch angle of the target link refers to the angle between the target link and the horizontal plane.

[0056] Step 102: Obtain, based on the corresponding relationship, an initial change trend of the angular velocity of the target link when the linear actuator moves at a constant speed;

[0057] In an optional embodiment, the angular velocity of the target link is obtained based on a derivative operation of the pitch angle of the target link.

[0058] Step 103: Adjust the moving speed of the linear actuator according to the initial variation trend of the angular velocity, so that the real-time variation trend of the angular velocity of the target link after adjustment is more stable than the initial variation trend.

[0059] In an optional embodiment, the control method further includes:

[0060] The moving speed of the linear actuator is adjusted according to the initial change trend of the angular velocity, so that the angular velocity change rate of the target link is less than the preset angular velocity change rate, or the angular velocity change rate of the target link is minimized.

[0061] In this embodiment, the preset angular velocity change rate is set according to actual conditions and is not specifically limited here.

[0062] In an optional embodiment, if Figure 2 As shown, step 103 includes:

[0063] Step 1031: Divide the moving stroke of the linear actuator into multiple sub-strokes;

[0064] Step 1032: Obtain each initial change trend of the angular velocity of the target connecting rod in each sub-stroke;

[0065] Step 1033: Adjust the moving speed of the linear actuator in each sub-stroke according to each initial change trend, so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend.

[0066] In this embodiment, in order to perform more precise and accurate control of the multi-link mechanism, specifically, by dividing the moving stroke of the linear actuator into multiple sub-strokes, the moving speed of the linear actuator in each sub-stroke is adjusted according to the obtained initial change trend of the angular velocity of the target link in each sub-stroke, so that the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend.

[0067] In an optional embodiment, the control method further includes:

[0068] Obtain the maximum angular velocity and the root mean square angular velocity of the target link;

[0069] The angular velocity change rate of the target link is calculated based on the maximum angular velocity and the root mean square of the angular velocity.

[0070] In an optional embodiment, the expression for the angular velocity change rate of the target link is calculated based on the maximum angular velocity and the root mean square of the angular velocity as shown in formula (1):

[0071]

[0072] Where M represents the rate of change of the angular velocity of the target link; F represents the maximum angular velocity of the target link; and N represents the root mean square of the angular velocity of the target link.

[0073] In an optional embodiment, if Figure 3 As shown, the multi-link mechanism is a four-link mechanism, which includes a first link L1, a second link L2, a third link L3 and a fourth link L4. The second link L2 is the target link. The first link L1, the second link L2, the third link L3, the fourth link L4 and the linear actuator L5 are connected to each other in sequence. Both end points of the second link L2 are not fixed. The first link L1, the third link L3 and the fourth link L4 all have one end point fixed and the other end point not fixed. One end point of the linear actuator L5 is fixed, and the other end point is connected to the fourth link L4. In a specific real-time process, when the moving distance S1 corresponding to the moving stroke of the linear actuator L5 changes, the first link L1 and the third link L3 rotate around their respective fixed points, as shown in FIG. Figure 3 As shown by the dotted line in the middle circle, the second link L2 will also rotate, and the motion trajectories of the two end points of the second link L2 are Figure 3 The expression for determining the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target link is shown in formula (2):

[0074]

[0075] Wherein, α represents the pitch angle of the target link, S1 represents the travel distance corresponding to the travel stroke of the linear actuator, L1 represents the length of the first link, L2 represents the length of the second link, L3 represents the length of the third link, L4 represents the length of the fourth link, L5 represents the length of the linear actuator, L6 represents the length between the fixed endpoint of the first link and the intersection of the second and third links, L7 represents the length between the fixed endpoint of the first link and the intersection of the third and fourth links, L8 represents the length between the fixed endpoint of the linear actuator and the intersection of the third and fourth links, ∠B1 represents the angle between the line connecting the fixed endpoint of the first link and the intersection of the third and fourth links and the line on which the third link lies, ∠B2 represents the angle between the line on which the third link lies and the line on which the fourth link lies, and ∠B3 represents the angle between the line connecting the fixed endpoint of the linear actuator and the intersection of the third and fourth links and a line perpendicular to the horizontal plane starting from the intersection of the third and fourth links.

[0076] Specifically, for example, Figure 4 As shown, A represents the intersection of the first link L1 and the second link L2, B represents the intersection of the second link L2 and the third link L3, C represents the intersection of the third link L3 and the fourth link L4, and C is also the fixed end point of the third link L3 and the fourth link L4, respectively. F represents the intersection of the fourth link L4 and the moving distance S1 corresponding to the moving stroke of the linear actuator, I represents the fixed end point of the first link L1, and G represents the fixed end point of the linear actuator. Figure 4 As shown, CE is the extension of BC, CH is perpendicular to GH, and CD is parallel to GH. The pitch angle α of the target link can be expressed as:

[0077]

[0078] like Figure 4 As shown, since the positions of the fixed end points I, C, and G are known, the angles of ∠ICD and ∠HCG are also known. In addition, since the third link L3, the fourth link L4, and ∠BCF are known, and CE is the extension line of BC, ∠BCF is also known. When the moving distance S1 corresponding to the moving stroke of the linear actuator changes, ∠FCG also changes. From the cosine law, we know that:

[0079]

[0080] From the above formula, we can know that:

[0081]

[0082] From the law of cosines we know that:

[0083]

[0084]

[0085]

[0086] From the above formula we can know that:

[0087]

[0088] Since the moving distance S1 and α corresponding to the moving stroke of the linear actuator in the above formula are variable, and other parameters are known, the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target link can be determined by the above formula.

[0089] In the specific implementation process, Figure 3 As shown in FIG1 , since the rotation center of the second link L2 is fixed, when the moving distance S1 corresponding to the moving stroke of the linear actuator L5 changes uniformly (i.e., the moving speed dS1 / dt of the linear actuator is constant), the change of the pitch angle α of the target link is non-uniform (i.e., the angular velocity dα / dt of the target link is a constant). Through kinematics, it can be obtained that when the linear actuator moves at a constant speed, the initial change trend of the angular velocity of the target link is as follows: Figure 5 As shown;

[0090] Depend on Figure 5 It can be seen that when the linear actuator moves at a constant speed, the angular velocity of the target link shows an initial U-shaped change trend with large ends and small in the middle. This indicates that when the moving speed of the linear actuator is constant, the angular velocity of the target link shows an initial change trend of large-small-large.

[0091] like Figure 6 As shown, in order to achieve more precise and accurate control of the multi-link mechanism, this embodiment divides the moving stroke of the linear actuator into multiple sub-strokes. By using a sensor provided on the linear actuator to monitor the length of each sub-stroke and the time required for the linear actuator to move within each sub-stroke, the moving speed of the linear actuator within each sub-stroke can be obtained. It should be noted that the moving speed of the linear actuator within each sub-stroke can be the same or different, so that within the entire moving stroke, the moving speed of the linear actuator presents an inverted U-shape, so that the angular velocity of the target link tends to be constant, and thus the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend. Specifically, Figures 5 to 6 The change of can intuitively show that the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend. Figure 5 and Figure 6 The vertical axis in represents the angular velocity of the target link, and the horizontal axis represents the moving data point. Further, Figure 5 and Figure 6 The waveform in the figure is obtained by processing the displacement data of three fixed points on the connecting rod using a 3D motion measurement system. Therefore, the horizontal axis has no units and can be understood as the moving data point. For example, the 3D motion measurement system starts measuring the moving data point at 0 and stops measuring at 4000. 0 or 4000 is just a scale. Assuming the 3D motion measurement system collects one data point every 0.01 seconds, 4000 indicates that 4000 data points were collected, with a total time of 40 seconds.

[0092] It should be noted that this embodiment does not require a velocity sensor or an inclination sensor to measure the angular velocity or angle of the target link of the multi-link mechanism, and thus does not require closed-loop velocity control, thereby reducing the requirements for the selection of the linear actuator.

[0093] In addition, the more segments the linear actuator's moving stroke is divided into, the smaller the angular velocity change rate of the target link is, and the more constant the angular velocity of the target link is, that is, the angular velocity change rate of the target link is negatively correlated with the number of the several segments.

[0094] This embodiment can reduce the angular velocity change rate of the target link of the multi-link mechanism without adding a speed sensor to the target link. Specifically, the correspondence between the moving stroke of the linear actuator and the pitch angle of the target link is determined; based on the correspondence, the initial change trend of the angular velocity of the target link when the linear actuator moves at a constant speed is obtained; and the moving speed of the linear actuator is adjusted based on the initial change trend of the angular velocity, so that the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend, thereby improving the control efficiency of the multi-link mechanism and reducing the control cost.

[0095] Example 2

[0096] This embodiment provides a control system for a multi-link mechanism, which includes a plurality of interconnected links and a linear actuator for driving the links to move. Figure 7 As shown, the control system includes: a first determination module 21, a second determination module 22, and a first adjustment module 23;

[0097] A first determining module 21 is used to determine the corresponding relationship between the movement stroke of the linear actuator and the pitch angle of the target connecting rod;

[0098] In this embodiment, when the movement stroke of the linear actuator changes uniformly, the change of the pitch angle of the target link is non-uniform.

[0099] It should be noted that the pitch angle of the target link refers to the angle between the target link and the horizontal plane.

[0100] A second determining module 22 is configured to obtain, based on the corresponding relationship, an initial change trend of the angular velocity of the target link when the linear actuator moves at a constant speed;

[0101] In an optional embodiment, the angular velocity of the target link is obtained based on a derivative operation of the pitch angle of the target link.

[0102] The first adjustment module 23 is configured to adjust the moving speed of the linear actuator according to the initial variation trend of the angular velocity, so that the real-time variation trend of the angular velocity of the target link after adjustment is more stable than the initial variation trend.

[0103] In an optional embodiment, if Figure 7 As shown, the control system further includes: a second adjustment module 24;

[0104] The second adjustment module 24 is used to adjust the moving speed of the linear actuator according to the initial change trend of the angular velocity, so that the angular velocity change rate of the target link is less than the preset angular velocity change rate, or the angular velocity change rate of the target link is minimized.

[0105] In this embodiment, the preset angular velocity change rate is set according to actual conditions and is not specifically limited here.

[0106] In an optional embodiment, if Figure 7 As shown, the first adjustment module 23 includes: a division unit 231, an acquisition unit 232, and an adjustment unit 233;

[0107] A dividing unit 231 is used to divide the moving stroke of the linear actuator into multiple sub-strokes;

[0108] an acquisition unit 232 for acquiring each initial change trend of the angular velocity of the target connecting rod within each sub-stroke;

[0109] The adjustment unit 233 is used to adjust the moving speed of the linear actuator in each sub-stroke according to each initial change trend, so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend.

[0110] In this embodiment, in order to perform more precise and accurate control of the multi-link mechanism, specifically, by dividing the moving stroke of the linear actuator into multiple sub-strokes, the moving speed of the linear actuator in each sub-stroke is adjusted according to the obtained initial change trend of the angular velocity of the target link in each sub-stroke, so that the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend.

[0111] In an optional embodiment, if Figure 7 As shown, the control system further includes: a first acquisition module 25 and a second acquisition module 26;

[0112] A first acquisition module 25 is used to obtain the maximum angular velocity and the root mean square angular velocity of the target connecting rod;

[0113] The second acquisition module 26 is configured to calculate the angular velocity change rate of the target link according to the maximum angular velocity and the root mean square of the angular velocity.

[0114] In an optional embodiment, the expression for the angular velocity change rate of the target link is calculated based on the maximum angular velocity and the root mean square of the angular velocity as shown in formula (1) in embodiment 1.

[0115] In an optional embodiment, if Figure 3 As shown, the multi-link mechanism is a four-link mechanism, which includes a first link L1, a second link L2, a third link L3 and a fourth link L4. The second link L2 is the target link. The first link L1, the second link L2, the third link L3, the fourth link L4 and the linear actuator L5 are connected to each other in sequence. Both end points of the second link L2 are not fixed. The first link L1, the third link L3 and the fourth link L4 all have one end point fixed and the other end point not fixed. One end point of the linear actuator L5 is fixed, and the other end point is connected to the fourth link L4. In a specific real-time process, when the moving distance S1 corresponding to the moving stroke of the linear actuator L5 changes, the first link L1 and the third link L3 rotate around their respective fixed points, as shown in FIG. Figure 3 As shown by the dotted line in the middle circle, the second link L2 will also rotate, and the motion trajectories of the two end points of the second link L2 are Figure 3 The expression for determining the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target link is shown in formula (2) in Example 1:

[0116] Specifically, for example, Figure 4 As shown, A represents the intersection of the first link L1 and the second link L2, B represents the intersection of the second link L2 and the third link L3, C represents the intersection of the third link L3 and the fourth link L4, and C is also the fixed end point of the third link L3 and the fourth link L4, respectively. F represents the intersection of the fourth link L4 and the moving distance S1 corresponding to the moving stroke of the linear actuator, I represents the fixed end point of the first link L1, and G represents the fixed end point of the linear actuator. Figure 4As shown, CE is the extension line of BC, CH is perpendicular to GH, and CD is parallel to GH. The expression for the corresponding relationship between the moving stroke of the linear actuator and the pitch angle of the target link can be derived from formulas (1.1)-(1.7) in Example 1.

[0117] In the specific implementation process, Figure 3 As shown in FIG1 , since the rotation center of the second link L2 is fixed, when the moving distance S1 corresponding to the moving stroke of the linear actuator L5 changes uniformly (i.e., the moving speed dS1 / dt of the linear actuator is constant), the change of the pitch angle α of the target link is non-uniform (i.e., the angular velocity dα / dt of the target link is a constant). Through kinematics, it can be obtained that when the linear actuator moves at a constant speed, the initial change trend of the angular velocity of the target link is as follows: Figure 5 As shown;

[0118] Depend on Figure 5 It can be seen that when the linear actuator moves at a constant speed, the angular velocity of the target link shows an initial U-shaped change trend with large ends and small in the middle. This indicates that when the moving speed of the linear actuator is constant, the angular velocity of the target link shows an initial change trend of large-small-large.

[0119] like Figure 6 As shown, in order to achieve more precise and accurate control of the multi-link mechanism, this embodiment divides the moving stroke of the linear actuator into multiple sub-strokes. By using a sensor provided on the linear actuator to monitor the length of each sub-stroke and the time required for the linear actuator to move within each sub-stroke, the moving speed of the linear actuator within each sub-stroke can be obtained. It should be noted that the moving speed of the linear actuator within each sub-stroke can be the same or different, so that within the entire moving stroke, the moving speed of the linear actuator presents an inverted U-shape, so that the angular velocity of the target link tends to be constant, and thus the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend. Specifically, Figures 5 to 6 The change of can intuitively show that the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend. Figure 5 and Figure 6 The vertical axis in represents the angular velocity of the target link, and the horizontal axis represents the moving data point. Further, Figure 5 and Figure 6The waveform in the figure is obtained by processing the displacement data of three fixed points on the connecting rod using a 3D motion measurement system. Therefore, the horizontal axis has no units and can be understood as the moving data point. For example, the 3D motion measurement system starts measuring the moving data point at 0 and stops measuring at 4000. 0 or 4000 is just a scale. Assuming the 3D motion measurement system collects one data point every 0.01 seconds, 4000 indicates that 4000 data points were collected, with a total time of 40 seconds.

[0120] It should be noted that this embodiment does not require a velocity sensor or an inclination sensor to measure the angular velocity or angle of the target link of the multi-link mechanism, and thus does not require closed-loop velocity control, thereby reducing the requirements for the selection of the linear actuator.

[0121] In addition, the more segments the linear actuator's moving stroke is divided into, the smaller the angular velocity change rate of the target link is, and the more constant the angular velocity of the target link is, that is, the angular velocity change rate of the target link is negatively correlated with the number of the several segments.

[0122] This embodiment can reduce the angular velocity change rate of the target link of the multi-link mechanism without adding a speed sensor to the target link. Specifically, the correspondence between the moving stroke of the linear actuator and the pitch angle of the target link is determined; based on the correspondence, the initial change trend of the angular velocity of the target link when the linear actuator moves at a constant speed is obtained; and the moving speed of the linear actuator is adjusted based on the initial change trend of the angular velocity, so that the real-time change trend of the angular velocity of the adjusted target link is more stable than the initial change trend, thereby improving the control efficiency of the multi-link mechanism and reducing the control cost.

[0123] Example 3

[0124] Figure 8 This is a schematic diagram of the structure of an electronic device provided in Example 3 of the present invention. The electronic device includes a memory, a processor, and a computer program stored in the memory and configured to run on the processor. When the processor executes the program, the control method of the multi-link mechanism of Example 1 is implemented. Figure 8 The electronic device 30 shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0125] like Figure 8 As shown, the electronic device 30 may be a general-purpose computing device, such as a server device. Components of the electronic device 30 may include, but are not limited to, the at least one processor 31, the at least one memory 32, and a bus 33 connecting different system components (including the memory 32 and the processor 31).

[0126] The bus 33 includes a data bus, an address bus, and a control bus.

[0127] The memory 32 may include a volatile memory, such as a random access memory (RAM) 321 and / or a cache memory 322 , and may further include a read-only memory (ROM) 323 .

[0128] The memory 32 may also include a program / utility 325 having a set (at least one) of program modules 324, such program modules 324 including but not limited to: an operating system, one or more application programs, other program modules, and program data, each of which or some combination may include an implementation of a network environment.

[0129] The processor 31 executes various functional applications and data processing by running the computer programs stored in the memory 32 , such as the control method of the multi-link mechanism of the first embodiment of the present invention.

[0130] The electronic device 30 may also communicate with one or more external devices 34 (e.g., a keyboard, a pointing device, etc.). Such communication may be performed via an input / output (I / O) interface 35. Furthermore, the model generating device 30 may also communicate with one or more networks (e.g., a local area network (LAN), a wide area network (WAN), and / or a public network, such as the Internet) via a network adapter 36. Figure 8 As shown, the network adapter 36 communicates with the other modules of the model-generated device 30 via the bus 33. It should be understood that, although not shown in the figures, other hardware and / or software modules may be used in conjunction with the model-generated device 30, including but not limited to microcode, device drivers, redundant processors, external disk drive arrays, RAID (RAID) systems, tape drives, and data backup storage systems.

[0131] It should be noted that although several units / modules or sub-units / modules of the electronic device are mentioned in the detailed description above, this division is merely exemplary and not mandatory. In fact, according to embodiments of the present invention, the features and functions of two or more units / modules described above may be embodied in a single unit / module. Conversely, the features and functions of a single unit / module described above may be further divided and embodied by multiple units / modules.

[0132] Example 4

[0133] This embodiment provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, the control method of the multi-link mechanism provided in embodiment 1 is implemented.

[0134] The readable storage medium may include, but is not limited to, a portable disk, a hard disk, a random access memory, a read-only memory, an erasable programmable read-only memory, an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0135] In a possible implementation manner, the present invention may also be implemented in the form of a program product, which includes program code. When the program product is run on a terminal device, the program code is used to enable the terminal device to execute the control method for the multi-link mechanism described in Example 1.

[0136] The program code for executing the present invention may be written in any combination of one or more programming languages, and may be executed entirely on the user device, partially on the user device, as a standalone software package, partially on the user device and partially on a remote device, or entirely on the remote device.

[0137] Although specific embodiments of the present invention have been described above, those skilled in the art will appreciate that these are merely illustrative and that the scope of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, and such changes and modifications are intended to fall within the scope of the present invention.

Claims

1. A control method for a multi-link mechanism, characterized in that: The multi-link mechanism includes a plurality of interconnected links and a linear actuator for driving the links to move. The control method includes: Determining a corresponding relationship between a movement stroke of the linear actuator and a pitch angle of a target connecting rod; Obtaining, according to the corresponding relationship, an initial change trend of the angular velocity of the target link when the linear actuator moves at a constant speed; The moving speed of the linear actuator is adjusted according to the initial change trend of the angular velocity, so that the real-time change trend of the angular velocity of the target link after adjustment is more stable than the initial change trend.

2. The control method of the multi-link mechanism according to claim 1, wherein: The control method further includes: The moving speed of the linear actuator is adjusted according to the initial change trend of the angular velocity, so that the angular velocity change rate of the target link is less than a preset angular velocity change rate, or the angular velocity change rate of the target link is minimized.

3. The control method of the multi-link mechanism according to claim 1, wherein: The angular velocity of the target link is obtained based on a derivative calculation of the pitch angle of the target link.

4. The control method of the multi-link mechanism according to claim 1, wherein: The step of adjusting the moving speed of the linear actuator according to the initial change trend of the angular velocity so that the real-time change trend of the angular velocity of the target link after adjustment is more stable than the initial change trend comprises: Dividing the moving stroke of the linear actuator into a plurality of sub-strokes; Obtaining each initial change trend of the angular velocity of the target connecting rod in each sub-stroke; The moving speed of the linear actuator in each sub-stroke is adjusted according to each initial change trend, so that the real-time change trend of the angular velocity of the target connecting rod after adjustment is more stable than the initial change trend.

5. The control method of the multi-link mechanism according to claim 2, wherein: The control method further includes: Obtaining the maximum angular velocity and the root mean square angular velocity of the target connecting rod; The angular velocity change rate of the target link is calculated according to the maximum angular velocity and the root mean square of the angular velocity.

6. The control method of the multi-link mechanism according to claim 1, wherein: The multi-link mechanism is a four-link mechanism, which includes a first link, a second link, a third link and a fourth link, the second link is the target link, and the first link, the second link, the third link, the fourth link and the linear actuator are connected to each other in sequence.

7. The control method of the multi-link mechanism according to claim 6, wherein: Both end points of the second connecting rod are not fixed, and one end point of the first connecting rod, the third connecting rod, and the fourth connecting rod are all fixed and the other end point is not fixed.

8. A control system for a multi-link mechanism, characterized in that: The multi-link mechanism includes a plurality of interconnected links and a linear actuator for driving the links to move. The control system includes: A first determining module is used to determine a corresponding relationship between a moving stroke of the linear actuator and a pitch angle of a target connecting rod; a second determining module, configured to obtain, based on the corresponding relationship, an initial change trend of the angular velocity of the target link when the linear actuator moves at a constant speed; An adjustment module is used to adjust the moving speed of the linear actuator according to the initial change trend of the angular velocity, so that the real-time change trend of the angular velocity of the target link after adjustment is more stable than the initial change trend.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and configured to run on the processor, wherein: When the processor executes the computer program, the control method of the multi-link mechanism according to any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the control method of the multi-link mechanism according to any one of claims 1 to 7 is implemented.

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